CNSW 1.0: Prefectural Reconstruction of China's Surface Water Resources Using Machine Learning Methods.

A comprehensive and long-term dataset of prefectural surface water resources is crucial for effective water resources management in China. However, there has been a significant gap in the availability of such datasets, with no existing datasets providing comprehensive long-term coverage. To address this gap, we have developed CNSW 1.0, the first long-term (2000-2020) dataset of prefectural surface water resources in China. Utilizing surface water resources data from official water resources bulletins, we employed 14 advanced machine learning models to reconstruct the CNSW 1.0 dataset. The resulting dataset exhibits high accuracy, with an R2 of 0.98 for total surface water resources and acceptable level of bias across China. CNSW 1.0 not only outperforms existing datasets like CNRD v1.0, GRUN, and ISIMIP in terms of simulation accuracy and spatial distribution but also fills a critical gap in water resources data for China. This dataset is expected to be an invaluable tool for developing more informed water resources management strategies at the administrative level in China, particularly in the context of climate change.